Voesen



bruise who.

WUFAUTURE OE SULFUR BEES.

Liiifilflflll.

lie Brewing.

To all whom 2 may concern:

Be it known that We, BIRGER FJELD HAL- vousuu and CHRISTIAN Homage, both subjects of the King of Norway, and residenbs of Christisnie, Norway, have invented certain new and useful Improvements in she Menuiecture ciiiul'fur Dyes; and we do hereby declare the following to be a full, clean, and exact description of the invention, such as will enable others skilled in the art to which it app-ermius to make and use the seme.

This invent-ion relates so the manufacture of. sulfur dyes and has for its obiect a process of producing dyes of this class having; brown color.

As is lruc considereble quantities of cyrool. are obtained as e. lay-product iii the manufacture of: cellulose according to .iahe

' sulfite process Hitherto :co greet importance has been attached so the jorcblem of recovering this substance, but lately attempts have been made to utilize it. These attempts have not, however for us lmown led to useful re sults. According to the QIESEHE invention cyzuol can now be employed for the manu facture oi dyes.v

This is obtained by converting the cymol into p-toluio ecid, nitretirig this substance to form uitrdcompounds, and then melting these compounds with polysulfids.

The cymol. may be converted into p-toluic cold by oxidation for iusbance by means of nitric sold. The nitration of this latter substance may suitably be edecied with a now ture' of nitric acid and sulfuric acid. By means of heading the iiisro-toluic ecide ob- .iained' hereby with pclyeulfids the ui'rro compounds sire converted into dyestuffs. The resulting melt is suitably dissolved in Waco-:1. From the solution the dye-studs could be precipiiaeted iii the usual manner, vim, by oxidation wish air or by means of acids. The micro-compounds obtained from the p-boluic acid can be employed Withoutspecial preperatiou. ll; is of advantage,

bpeclficatiou of Letters Iateirt. -]Pa,fi;en'b9d July 22 1919, dpph'coticn filed November 23, 191$. la'erial No. 263,906.

however, to produce the monoand di-nitro compounds separately because it is hereby made more easy to produce the desired shade of color. When for instance mononitrotoluic acid is used in the sulfur melt the fglllowing proportions are found to be suita. e:

50 gramnitro'pera-toluic acid,

170 gram sulfid of sodium,

60 gram of sulfur, and

50 gram Water V are heated on an oil both during 12 hours up to about 250 C.v Hereby is obtained a dye-stud which on cotton directly produces a dark chestnut color.

When di-nitrotoluic acid is'employed in the sulfur melt for instance in the follow-- ing proportion:

40 gram di-nitro-p-toluic acid,

M0 gram sulfiol of sodium,

gram of sulfur,

50 am of water I heats on do oil bath for 12 hours at a temperature up-co about 250 C. a dye stud is obtained, which also produces a brown color directly on cotton. 1

We clsiyh: I

l. Proq ees for the manufacture of brown. sulfur dyes w ip-rising the steps of melting nitro compounds of p-toluic acid with poly- BIRGER FJELQ HALVORSEN. CHRISTIAN HORBYE.

Witnesses:

C. NORMAN, C. FABRICIUS HANSEN. 

